Plateau Mountain: a case study of alpine permafrost in the Canadian Rocky Mountains
Investigations of alpine permafrost in the Western Cordillera of Canada were initiated in 1974 on Plateau Mountain located in the front ranges of the Rocky Mountains 80 km southwest of Calgary, Alberta. Thermocouple and thermistor cables to measure ground temperatures were installed in boreholes to...
| Main Authors: | , |
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| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
1978
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| Subjects: | |
| Online Access: | https://nrc-publications.canada.ca/eng/view/ft/?id=9ed5a9bf-846b-4e77-bfb2-761a663bb06e https://nrc-publications.canada.ca/eng/view/object/?id=9ed5a9bf-846b-4e77-bfb2-761a663bb06e https://nrc-publications.canada.ca/fra/voir/objet/?id=9ed5a9bf-846b-4e77-bfb2-761a663bb06e |
| Summary: | Investigations of alpine permafrost in the Western Cordillera of Canada were initiated in 1974 on Plateau Mountain located in the front ranges of the Rocky Mountains 80 km southwest of Calgary, Alberta. Thermocouple and thermistor cables to measure ground temperatures were installed in boreholes to depths of 15 to 30 m on the summit above treeline at 2519 m elevation and down the forested mountain side to 2103 m elevation. Monthly observations on these cables and temperature checks in an ice cave confirm the existence of permafrost (-1.0 to -1.5 degrees C). The mean annual air temperature at the summit is -4.1 degrees C and strong winds remove most of the snow. Temperature measurements indicate that permafrost extends to a depth of possibly 100 m or more, the upper portion having adjusted to the present climate and the lower layers being relic. On a entrepris en 1974 une étude du pergélisol alpin de la cordillère Occidentale canadienne, sur le mont Plateau, qui fait partie des chaînons frontaux des montagnes Rocheuses à 80 km au sud-ouest de Calgary, en Alberta. On a installé des câbles de thermocouples et thermistors destinés à mesurer la température du sol dans des trous de sondage de 15 à 30 m de profondeur forés à 2159 m d'altitude, au sommet, lequel dépasse la limite supérieure des arbes, et sur le versant boisé de la montagne jusqu'à 2103 m d'altitude. Des observations effectuées chaque mois sur ces câbles, ainsi que les relevés de température obtenus dans une caverne de glace confirment l'existence du pergélisol (-1. 0 à -1.5 degrés C). La température atmosphérique annuelle moyenne est de -4.1 degrés C au sommet, et des vents violents enlèvent la plus grande partie de la neige. Des mesures de température indiquent que le pergélisol atteint au moins 100 m de profondeur, et que la portion supérieure de celui-ci subit l'influence du climat actuel, tandis que les couches inférieures sont des couches relictes. Peer reviewed: No NRC publication: Yes |
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